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Hello please help help

Hello please help help-example-1

1 Answer

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9514 1404 393

Answer:

48°

Explanation:

ΔACB is isosceles, so angles A and B have the same measure. The measure of angle C in that triangle is ...

∠C = 180° -2(69°) = 42°

Angle C in ΔCDE has the same measure. Angle D is the complement of that:

∠D = 90° -42° = 48°

_____

The relations we used are ...

  • the sum of angles in a triangle is 180°
  • base angles of an isosceles triangle are congruent
  • vertical angles are congruent
  • acute angles in a right triangle are complementary
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